Ventilator apparatus

ABSTRACT

One or more embodiments of the presently described invention provides a ventilator including a timing device, an electric power source and a flow control device. The timing device is electronically controlled and is capable of controlling a period of time that a fluid is delivered to a patient. The timing device can control this period of time using a solenoid. The flow control device controls a rate of flow that the fluid is delivered to the patient. The flow control device can control the rate of flow using a plurality of orifices. The timing device and flow control device are separate from one another and each is capable of being operated independent of the other.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/810,214, which was filed on 5 Jun. 2007, and is entitled “VentilatorApparatus” (the “'214 application”). The entire disclosure of the '214application is incorporated by reference.

BACKGROUND

The presently described invention generally relates to artificialbreathing devices. More specifically, embodiments of the presentlydescribed technology provide an improved ventilator apparatus.

Emergency ventilators are devices that can partially or entirely replacebag mask resuscitation devices as a manner of providing mechanicalventilation in an emergency environment. Existing devices can permit theuser, such as an EMT or paramedic, to set a tidal volume (“V.sub.T”) andbreaths per minute (“BPM”) and little more, if anything. These existingdevices are usually driven or powered by oxygen under pressure flowingfrom portable compressed oxygen cylinders.

Existing hospital ventilators can be difficult to use by individuals whoare not as highly trained as respiratory therapists. In addition,existing ventilators can be very expensive. Given new requirements onhospitals to prepare for events such as terrorist attacks, naturaldisasters or an outbreak of disease such as avian flu adding largenumbers of ventilators can be a large financial burden and havingadequate trained staffing during such a crisis can be a bigger problem.

Existing ventilators typically are controlled by a complex electronicsystem (“electric-only ventilators”) or by a complex system ofpneumatics (“pneumatically-only ventilators”). With respect to theelectric-only ventilators, these devices suffer from many drawbacks. Forexample, electric-only ventilators usually include a fragile electronicsystem of circuits used to control inspiration time and fluid flowthrough the ventilator. As a result, these types of ventilators tend tobe relatively fragile when compared to pneumatically controlledventilators. As emergency ventilators are typically used in emergencysituations, the durability of the ventilators is of considerableimportance.

Electric-only ventilators also usually include electronic circuits tocontrol and drive a complex proportioning valve to set the fluid flowthrough the ventilator. Controlling such a valve typically requires aconsiderable amount of electric power. As a result, electric-onlyventilators are usually powered by a lead acid or lithium ion battery.These types of batteries are relatively heavy and are not easilyaccessible during emergency situations. That is, in an emergencysituation, a supply of lead acid or lithium ion batteries may not bereadily available. Moreover, existing electric-only ventilators candeplete a lead acid or lithium ion battery fairly quickly. Manyventilators can deplete such a battery in under eight hours.

In addition, use of such a valve typically requires one or more positionfeedback circuits to achieve the accuracy required of a ventilator. Theadded complexity of position feedback circuits only adds to the cost ofthese types of ventilators.

With respect to pneumatic-only ventilators, these devices tend to bemore durable than electric-only ventilators (most likely because they donot include the complex circuitry of electric-only ventilators). But,pneumatic-only ventilators usually must be very closely monitored duringoperation. These ventilators use a system of pneumatics powered by thefluid being delivered to the patient to control timing and flow of thefluid through the ventilator. That is, the ventilators use a build up ofpressure in the device as a timing function. With small leaks and/orchanges in the source fluid pressure, the timing function and thus theventilator can suffer from poor precision and/or accuracy. Pneumaticventilators cost less than complex electronic ventilators but still costseveral thousand dollars due to the pneumatic components required.

While some more inexpensive ventilators have been introduced into themarket, these ventilators also suffer from drawbacks. For example, oneor more of these ventilators do not include any feedback to a user ofthe ventilator. That is, a user cannot determine the BPM or volume offluid being delivered to a patient. The user must externally calculatesuch information using, for example, a stopwatch to determine the totaltime of inspiration. With such ventilators, a single user cannot assistmore than one person in emergency situations. The user must stay with aventilator to continually monitor its delivery of fluid to a user.

Thus, a need exists for an improved ventilator that is cheaper tomanufacture, more durable, more precise and more accurate.

BRIEF DESCRIPTION

One or more embodiments of the presently described invention provides aventilator including a timing device, an electric power source and aflow control device. The timing device is capable of controlling aperiod of time that a fluid is delivered to a patient. The timing devicecan control this period of time using a solenoid. The flow controldevice controls a rate of flow that the fluid is delivered to thepatient. The flow control device can control the rate of flow using aplurality of orifices.

One or more embodiments of the presently described invention alsoprovides a method for providing improved control of a ventilator. Themethod includes the steps of electronically controlling a period of timethat a fluid is delivered to a patient using a solenoid, controlling arate of flow that the fluid is delivered to the patient by directing thefluid through at least one of a plurality of orifices having a pluralityof different diameters, and providing a volume of the fluid to thepatient by permitting the fluid to pass through the ventilator at therate of flow for the period of time.

One or more embodiments of the presently described invention alsoprovide a ventilator including an inspiratory timing control device anda plurality of orifices. The timing control device is configured tostart and stop a flow of fluid through the ventilator and is powered byat least one battery. The orifices include different diameters and areconfigured to control a rate of fluid flow through the ventilator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a diagram of a ventilator system in accordance withan embodiment of the presently described invention.

FIG. 2 illustrates a view of the ventilator in accordance with anembodiment of the presently described invention.

FIG. 3 illustrates a view of the power source chamber of the ventilatordevice in accordance with an embodiment of the presently describedinvention.

FIG. 4 illustrates a view of inside the ventilator in accordance with anembodiment of the presently described invention.

FIG. 4A illustrates a view of one half of the inside of the ventilatorin accordance with an embodiment of the presently described invention.

FIG. 4B illustrates a view of the other half of the inside of theventilator in accordance with an embodiment of the presently describedinvention.

FIG. 5A illustrates a perspective view of a back side and a top of aflow control device in accordance with an embodiment of the presentlydescribed invention.

FIG. 5B illustrates a perspective view of a front side and a top of aflow control device in accordance with an embodiment of the presentlydescribed invention.

FIG. 5C illustrates a plan view of a side of a flow control device inaccordance with an embodiment of the presently described invention.

FIG. 5D illustrates a plan view of the back side of a flow controldevice in accordance with an embodiment of the presently describedinvention.

FIG. 6 illustrates a cross-sectional view of the flow control device inaccordance with an embodiment of the presently described invention.

FIG. 7 illustrates a schematic diagram of a solenoid in an open positionin accordance with an embodiment of the presently described invention.

FIG. 8 illustrates a schematic diagram of a solenoid in a closedposition in accordance with an embodiment of the presently describedinvention.

FIG. 9 illustrates a flowchart of a method for using an improvedventilator in accordance with an embodiment of the presently describedinvention.

FIG. 10A illustrates a view of tubing capable of being used as a patientcircuit connection in accordance with an embodiment of the presentlydescribed invention.

FIG. 10B illustrates a view of a plurality of tubing sections forming acontinuous connection in accordance with an embodiment of the presentlydescribed invention.

FIG. 11 illustrates an orifice plate in accordance with an embodiment ofthe presently described invention.

FIG. 12 illustrates an exploded view of the ventilator in accordancewith an embodiment of the presently described invention.

FIG. 13 illustrates a cross-section view of the flow control device inaccordance with an embodiment of the presently described invention.

The foregoing summary, as well as the following detailed description ofcertain embodiments of the presently described technology, will bebetter understood when read in conjunction with the appended drawings.For the purpose of illustrating the presently described technology,certain embodiments are shown in the drawings. It should be understood,however, that the presently described technology is not limited to thearrangements and instrumentality shown in the attached drawings.

DETAILED DESCRIPTION

FIG. 1 illustrates a diagram of a ventilator system 100 in accordancewith an embodiment of the presently described invention. Ventilatorsystem 100 includes a ventilator device 110, a fluid source 120, a fluidsource connection 130, a patient circuit connection 140, a deliverydevice 150, an output valve 170 and an input or inlet valve 180. Asshown in FIG. 1, ventilator system 100 is connected to a patient 160.

Fluid source 120 is connected to ventilator 110 by way of fluid sourceconnection 130. Ventilator 110 is connected with delivery device 150 byway of patient circuit connection 140. Delivery device 150 is connectedto patient 160. In an embodiment, delivery device 150 includes anexhalation port 155 and/or a one-way valve 157. One-way valve 157 caninclude a valve that only permits the flow of fluid in one directionthrough valve 157 and, once the pressure of the fluid flowing throughvalve 157 drops a sufficient amount, valve 157 closes. For example,one-way valve 157 can comprise a duck valve or duck bill valve.

Fluid source 120 can include any container holding a fluid that is to bedelivered to patient 160 using ventilator 110. For example, fluid source120 can include a canister of pressurized gas. In an embodiment, fluidsource 120 includes a pressurized canister of oxygen. In anotherembodiment, fluid source 120 includes a 280 kPa (40.6 psi) to 600 kPa(87.0 psi) oxygen canister. In another embodiment, fluid source 120includes a 344 kPa (50.0 psi oxygen canister with a minimum of 40 litersper minute flow capacity. In another embodiment, fluid source 120includes a high flow air and oxygen blender. In an embodiment, fluidsource 120 includes a diameter index safety system (“DISS”) fitting. Thefluid canisters may contain gas at high pressures such as 2000 or higherand deliver gas at 280 kPa (40.6 psi) to 600 kpa (87.0 psi) by using afluid regulator to reduce the pressure.

Fluid source connection 130, or patient airway connection 130, includesany tube or hose capable of connecting to fluid source 120 and inletvalve 180. For example, fluid source connection 130 can include a supplyhose made of polyvinyl chloride (“PVC”). In another example, fluidsource connection 130 can include a supply hose made of rubber.

Patient circuit connection 140 includes any tube or hose capable ofconnecting to output valve 170 and delivery device 150. For example,patent circuit connection 140 can include corrugated tubing. The tubingcan be manufactured from a material such as ethylene-vinyl acetate(“EVA”).

In an embodiment, the tubing used for patient circuit connection 160 isa continuous piece that includes sections capable of being separatedfrom one another to form shorter pieces. For example, patient circuitconnection 160 can be separated at any point approximately 6″ from anyother point so that any length that is an increment of 6″ can be madefrom the continuous tube.

FIG. 10A illustrates a view of sectional tubing 930 capable of beingused as patient circuit connection 160 in accordance with an embodimentof the presently described invention. FIG. 10B illustrates a pluralityof tubing sections 930 forming a longer, continuous connection 160.

Delivery device 150 includes any apparatus, device or system capable ofreceiving fluid from ventilator 110 via patient connection circuit 140and delivering or providing the fluid to patient 160. For example,delivery device 150 can include an oxygen mask or endotracheal tube. Inan embodiment, delivery device 150 includes an oxygen mask with a 22 mminside diameter. In another embodiment, delivery device 150 includes anendotracheal tube with a 15 mm outside diameter.

Output valve 170 includes any outlet, valve, connection or openingcapable of providing fluid communication between ventilator 110 andpatient communication circuit 140. For example, output valve 170 caninclude a valve providing a connection between ventilator 110 andpatient connection circuit 140 that permits fluid to flow fromventilator 110 to patient connection circuit 140. In an embodiment,output valve 170 includes a 22 mm connection valve. In an embodiment,output valve 170 includes an anti-suffocation valve.

Input valve 180 includes any outlet, valve, connection or openingcapable of providing fluid communication between fluid source connection130 and ventilator 110. For example, input valve 180 can include a valveproviding a connection between fluid source connection 130 andventilator 110 that permits fluid to flow from fluid source connection130 to ventilator 110. In an embodiment, input valve 180 includes a DISSfitting. In an embodiment, input valve 180 includes a filter. Forexample, input valve 180 can include a 65 micron sintered bronze filter.

In operation, fluid source 120 and ventilator 110 are connected toopposing ends of fluid source connection 130. Fluid source connection130 can be connected to input valve 180 attached to ventilator 110.

Ventilator 110 and delivery device 150 are connected to opposing ends ofpatient circuit connection 140. Patient circuit connection 140 canconnect to output valve 170 attached to ventilator 110.

A user selects an inspiratory time (“I_(t)”). The details of how a userselects the inspiratory time are described below. In short, a useremploys one or more buttons on ventilator 110 to select one of aplurality of inspiratory times. In an embodiment, a user selects a oneor two second inspiratory time. For example, a user can select a onesecond inspiratory time for using ventilator 110 on a child or adultwith a tidal volume requirement of 600 mL or less. In another example, auser can select a two second inspiratory time for using ventilator 110on an adult with a tidal volume requirement of more than 400 mL.

A user also selects breaths per minute (“BPM”). The details of how auser selects the BPM are described below. In short, a user employs oneor more buttons on ventilator 110 to select one of a plurality of BPMs.In an embodiment, a user selects a BPM from eight to thirty. In anembodiment, the range of available BPMs can be limited based on theinspiratory time selected by the user. For example, for a one secondinspiratory time, the range of available BPMs can be eight to thirty ortwelve to twenty. In another example, for a two second inspiratory time,the range of available BPMs can be eight to twenty or eight to twelve.

A user also selects a tidal volume (“T_(v)”). The selected tidal volumedetermines a rate of flow of fluid through ventilator 110 and/ordelivered to patient 150. The details of how a user selects the tidalvolume are described below. In short, a user employs a knob ofventilator 110 to select one of a plurality of tidal volumes. In anembodiment, the available tidal volumes and corresponding rate of flowis limited based on the selected inspiratory time. For example, thetidal volume settings available for a user to select and thecorresponding rate of flow can be limited to those shown in the belowtable:

Tidal Volume Setting (“T_(v)”) in mL Rate of Flow in Liters per I_(t) =1 second I_(t) = 2 seconds Minute (“LPM”) 200 400 12 240 480 14.4 280560 16.8 320 640 19.2 360 720 21.6 400 800 24 440 880 26.4 480 960 28.8520 1040 31.2 560 1120 33.6 600 1200 36

The user then connects ventilator 110 to patient 160 using patientconnection circuit 140 and delivery device 150. Ventilator 110 thenprovides tidal volumes to patient 160 at the selected BPMs. In anembodiment, if patient 160 begins to breathe spontaneously or on his orher own, the anti-suffocation valve included in output valve 170 permitsambient air to be pulled in through valve 170. In another embodiment, asensor capable of detecting a spontaneous patient breath can be added tooutput valve 170. Such a sensor can detect a spontaneous breath bydetecting negative pressure in output valve 170. When negative pressureis so detected, ventilator 110 then provides the selected tidal volumesto patient 160 and adjusts the timing to continue at the selected BPMsafter the spontaneous breath is delivered.

In an embodiment, ventilator 110 includes a plurality of alarms. Forexample, ventilator 110 can include one or more alarms that becomeactivated when a fluid or gas pressure in patient connection circuit 130(or patient airway connection 130) exceeds a threshold (or upper airwaypressure threshold), fluid or gas pressure in patient connection circuit130 (or patient airway connection 130) falls below a threshold (or lowerairway pressure threshold), the pressure of the fluid or gas supplied bysource 120 falls below a threshold (or source pressure threshold),and/or a level of the power source for ventilator 110 falls below athreshold (or power source threshold). Two or more of these thresholdscan be the same numeric value or can be different from the otherthresholds. The details on how these alarms function is described inmore detail below. Each alarm can include a visual and/or audiblenotification such as a light and/or a buzzer. In an embodiment,ventilator 110 can include a button or switch on control panel 210 or analarm panel 220 that stops one or more activated alarms. For example, abutton or switch similar to time control buttons 216 or BPM controlbuttons 218 can be pressed to dim a light or end a buzzer that isactivated as an alarm. In an embodiment, pressing the button or switchto stop the alarm temporarily stops the alarm for a given time period.After the given time period, the alarm will resume if the event forwhich the alarm was first activated has not been remedied. In anotherembodiment, pressing the button or switch to stop the alarm only stopsan audible alarm but does not stop any visual alarm.

In an embodiment, the threshold or upper airway pressure threshold forthe fluid or gas pressure in patient connection circuit 130 is less thanor equal to 52 cm H₂O (5.1 kPa). That is, the upper airway pressurethreshold is no more than 52 cm H₂O (5.1 kPa). For example, thethreshold can be 52 cm H₂O (5.1 kPa).

In an embodiment, ventilator 110 can include a safety pressure reliefmechanism. This mechanism can relieve pressure in ventilator 110 whenthe internal pressure exceeds the upper airway pressure threshold. Thesafety pressure relief mechanism can be embodied in a pressure reliefplate, spring and outlet port. For example, the safety pressure reliefmechanism can be embodied in pressure relief plate 630, spring 635 andoutlet port 640 described below with respect to device 434 and FIG. 6.

In an embodiment, an alarm that occurs when the pressure in patientairway connection 130 exceeds a threshold ends or is cleared when apredetermined amount of time passes with the upper airway pressure beinglower than the threshold. In other words, after the pressure inconnection 130 exceeds the upper airway pressure threshold, the alarm isactivated and stays active (that is, continues with an audible and/orvisual notification to a user). The alarm continues in its active stateuntil the pressure drops below the upper airway pressure threshold andstays below the threshold for a predetermined amount of time. Forexample, if the pressure drops below a threshold of 52 cm H₂O (5.1 kPa)for at 25 seconds, the alarm ends or becomes cleared.

In an embodiment, the lower airway pressure threshold for the fluid orgas pressure in patient connection circuit 130 is 5 cm H₂O (493 Pa). Inaddition, there can be a minimum time span at which the fluid pressurein the patient connection circuit 130 must be at or below the thresholdbefore the alarm is activated. For example, the alarm can be set not toactivate unless the pressure in patient connection circuit 130 is at orbelow 5 cm H₂O (493 Pa) for at least 15 seconds.

In an embodiment, the alarm that is activated when the pressure of thefluid or gas supplied by source 120 falls below a threshold of 40 psi(275 kPa). In another embodiment, this threshold is 38 psi (262 kPa). Inaddition, the alarm can remain activated until this pressure rises abovethe predetermined threshold for a predetermined amount of time. In anembodiment, this amount of time is 15 seconds.

In an embodiment, the alarm that is activated when the level of thepower source for ventilator 110 falls below a threshold becomesactivated when a minimum amount of time of power is left in the source.That is, the alarm is triggered when the power source can only powerventilator 110 for a minimum amount of time. The minimum amount of timecan be calculated by determining the voltage level remaining in thepower source capable of operating ventilator 110 for the minimum amountof time. In an embodiment, this minimum amount of time is two hours. Inother words, this alarm is activated when only two hours of batterypower remains to power ventilator 110. In another embodiment, the alarmis triggered when the voltage remaining in the power source falls belowa threshold. For example, the alarm can be triggered when apredetermined amount of voltage remains in one or more battery powersources. These power source alarms can be deactivated or cleared whenthe power source is replenished so that more than the predeterminedminimum amount of time or voltage remains in the power source.

In an embodiment, one or more of these alarms is a visual indicator,such as a light. For example, an alarm can be a light emitting diode(“LED”) that is illuminated when the alarm is activated and is notilluminated when the alarm is not activated. In another embodiment, oneor more of these alarms is an audible notification. For example, analarm can be a beep or repeated beeping sound that occurs when the alarmis activated and is silent when the alarm is not activated.

FIG. 2 illustrates a view of ventilator 110 in accordance with anembodiment of the presently described invention. Ventilator 110 includesa control panel 210, an alarm panel 220, an on/off switch 230, a tidalvolume control knob 240 and a power source door 250.

Control panel 210 includes a BPM display window 212, an airway pressurewindow 214, inspiratory time control buttons 216 (also referred to asinspiratory buttons 216) and BPM control buttons 218 (also referred toas BPM buttons 218). While only two buttons are shown for each ofinspiratory buttons 216 and BPM buttons 218, a larger number of buttonscan be used for either set of buttons in accordance with an embodimentof the presently described invention.

Alarm panel 220 includes one or more visual indicators of one or morealarms. In the embodiment shown in FIG. 2, alarm panel 220 includesthree LEDs, one for each of the high airway pressure alarm, the lowsource gas (or fluid pressure) alarm and the low battery (or powersource) alarm. In addition, one or more of the LEDs can flash toindicate a low pressure alarm (such as when the fluid or gas pressure inpatient airway connection 130 falls and stays below a threshold for agiven amount of time. For example, this time can be 15 seconds, butother times can be used.

FIG. 3 illustrates a view of a power source chamber 310 of ventilator110 in accordance with an embodiment of the presently describedinvention. Power source chamber 310 is a recessed area of ventilator 110that is configured to hold and electrically connect an electric powersource to ventilator 110. In an embodiment, chamber 310 can be accessedby removing power source door 250. For example, power source chamber 310can include a recess with electrical connections or wires 520 for one ormore power sources 320, as shown in FIG. 3.

In an embodiment, device 110 includes an electrical timing system ordevice (described in more detail below) that is capable of operating offof a relatively small amount of voltage or current. For example, theelectrical timing device can operate off of 3.0 volts or less of directcurrent.

In an embodiment, power sources 320 include alkaline batteries. Forexample, the electrical timing device can operate off of the voltage orcurrent supplied by two size “D” alkaline batteries. By enabling thetiming device to operate off of common alkaline batteries, is becomesconsiderably more simple to find a power source 320 for ventilatordevice 110 in an emergency situation. In addition, existing ventilatorsuse lead acid batteries as electrical power sources. These batteries arelarge, heavy and difficult to find when compared to alkaline batteries.While two size “D” alkaline batteries can be used, other types andcombination of batteries can also be used. For example, a singlealkaline or lithium battery (or any other battery capable of providingvoltage), or any combination of batteries capable of providing theminimum voltage required to operate ventilator 110 can be used. In anembodiment, ventilator 110 can be supplied with three or less volts byone or more batteries. These volts can be stepped up by a voltagestep-up circuit. Alternatively, ventilator 110 can be supplied with morethan three volts by one or more batteries and not require any voltagestep-up circuitry.

In an embodiment, power source(s) 320 enables the timing device ofventilator 110 to operate for at least eight hours at room temperature,assuming that a fluid source 120 does not expire before the eight hoursis completed. In a preferred embodiment, power source(s) 320 enable thetiming device to operate continuously for at least eight hours at roomtemperature (again, assuming fluid source 120 does not become depletedbefore then). In a more preferred embodiment, two alkaline batteries(such as size “D” alkaline batteries, for example) acting as powersources 320 enable the timing device to operate continuously for atleast eight hours at room temperature (again, assuming fluid source 120does not become depleted before then).

In an embodiment, power source(s) 320 enables the timing device ofventilator 110 to operate for at least twelve hours at room temperature,assuming that a fluid source 120 does not expire before the twelve hoursis completed. In a preferred embodiment, power source(s) 320 enable thetiming device to operate continuously for at least twelve hours at roomtemperature (again, assuming fluid source 120 does not become depletedbefore then). In a more preferred embodiment, two alkaline batteries(such as size “D” alkaline batteries, for example) acting as powersources 320 enable the timing device to operate continuously for atleast twelve hours at room temperature (again, assuming fluid source 120does not become depleted before then).

In an even more preferred embodiment, power source(s) 320 enable thetiming device to operate for at least forty-eight hours at roomtemperature (again, assuming fluid source 120 does not become depletedbefore then). In an even more preferred embodiment, power source(s) 320enable the timing device to operate continuously for at leastforty-eight hours at room temperature (again, assuming fluid source 120does not become depleted before then). In an even more preferredembodiment, two alkaline batteries (such as size “D” alkaline batteries,for example) acting as power sources 320 enable the timing device tooperate continuously for at least forty-eight hours at room temperature(again, assuming fluid source 120 does not become depleted before then).By “operating” and “operate,” it is meant that power source 320 providessufficient power to ventilator 110 so that ventilator 110 can deliverone or more breaths to a patient 160.

In an embodiment, on/off switch 230 is used to activate or deactivatecircuit 514. That is, when switch 230 is pressed so as to turnventilator 110 “on,” power is supplied to circuit 514 from power source320. Conversely, when switch 230 is pressed so as to turn ventilator 110“off,” power is no longer supplied to circuit 514 from power source 320.

FIG. 12 illustrates an exploded view of ventilator 110 in accordancewith an embodiment of the presently described invention. Ventilator 110includes a plurality of panels 1210, 1220 and 1230, a plurality ofscrews 1240, power source 320, a plurality of electrical contacts 1250,two halves 400 and 500 of ventilator 11 housing, a plurality of clips1260, output valve 170, an anti-suffocation valve 1270, a plurality ofwashers 1280, a pressure relief valve 1290, a screw cover 1212, an elbowfitting 1214, a ball and spring combination 435, a regulator connector1216, circuit 514, flow control device 434, regulator 414, input/inletvalve 180, solenoid 416, Y-connector 420, solenoid barb 436, a decal1218, knob 240, control panel 210, alarm panel 220 and an o-ring 1282.Ventilator 110 also can include one or more filters 1284 and/or nuts1286. Filters 1284 can be inserted into an input or output orifice ofventilator 10. For example, a filter 1284 can be inserted into inputvalve 180 to filter out some or all impurities in the fluid supplied toventilator 110 through input valve 180.

Panels 1210, 1220 and 1230 can be combined to form power source door250.

Subsets of plurality of screws 1240 are configured to perform severalfunctions. For example, screws 1240 can be used to: (a) hold panels1210, 1120 and 1230 together and to enclose power source chamber 310,(b) hold ventilator halves 400, 500 together using clips 1260, (c) holdsolenoid 416 in place in one half of ventilator housing 400, (d) connectknob 240 with protrusion 610 and/or (e) mount flow control device 434 tohousing 400. As shown in FIG. 12, different sizes and lengths of screws1240 can be used to achieve the various functions listed above, as wellas other functions. Additionally, one or more screws 1240 can be used incombination with one or more nuts 1286 in order to provide a more secureconnection, as shown in FIG. 12.

Electrical contacts 1250 are each configured (or configured to operatetogether) to permit power to be transferred from power source 320 towires 520. For example, electrical contacts 1250 can be sections of anelectrically-conductive material (such as a metal) connected to poles ofbatteries as power source 320 and to wires 520.

Various ones of the plurality of washers 1280 are configured and placedto provide an improved seal around the components each is placed aroundor against, as shown in FIG. 12, and/or to hold one or more screws 1240in place. Also as shown in FIG. 12, washers 1280 can be different sizesin order to accommodate different sized components, openings or screws1240 in ventilator 110.

O-ring 1282 is placed to create a partial or complete seal around knob240. By placing o-ring 1280 as shown in FIG. 12, o-ring 1282 can impedeand/or prevent water or other fluids from entering ventilator 110 nearknob 240.

Screw cover 1212 is configured to be placed over screws 1240 that holdsolenoid 416 in place. Cover 1212 can cover these screws 1240 forprotection of screws 1240 from static discharge and/or tampering, andfor a more aesthetically pleasing appearance.

Regulator connector 1216 is configured to provide a fluid communicationpath from regulator 414 to tube 426. Fitting 1214 is another connectorthat is similar to connector 1216. Fitting 1214 comprises an elbow witha barb on one end and a thread on the other end. Fitting 1214 can beidentical to connector 1216 with a different thread size. The barbincludes an outlet such as a tube or other opening in fitting 1214.

Decal 1218 is configured to provide visual reference marks so a user canknow which direction to rotate knob 240 and how far to rotate knob 240to obtain a desired flow rate through device 434. In other words, decal1218 can include markings of flow rates that correspond to an orifice622 selected by rotating knob 240 to a given position, as shown in FIGS.1 and 2.

Anti-suffocation valve 1270 is a valve capable of opening to allowoutside atmosphere (for example, air) to patient 160 via connectioncircuit 140. Valve 1270 can be configured so as to only provide outsideatmosphere to patient 166 if patient 160 attempts to breathe on his orher own and ventilator 110 is off or otherwise unable to deliver abreath to patient 160 at that time.

Valve 1290 is a valve capable of impeding or preventing a buildup ofpressure inside ventilator 110. For example, the fluid provided topatient 160 by ventilator 110 can leak into the inside of ventilator110. When this occurs, the fluid pressure inside ventilator 110 canbuildup. In order to prevent this buildup of pressure from damagingventilator 110 or any components of ventilator 110, valve 1290 can openwhen the fluid pressure exceeds a predetermined threshold and permit thefluid inside ventilator 110 to escape to the surrounding atmosphere.

Ball and spring combination 435 includes a ball connected to one end ofa spring. Combination 435 is inserted in flow control device 434 so thatthe ball of combination 435 sticks out of device 434. Knob 240 caninclude a plurality of indentations on the back side of knob 240. Theseindentations are preferably located to match up with each of a pluralityof markings 242 on knob 240 (described in more detail below). Byrotating knob 240, ball and spring combination 435 push a ball againstthe indentations in knob 240. As the indentations pass by combination435, a user who is rotating knob 240 can feel and/or hear the ball as itis pressed in each of the indentations. In addition, the ball and springcombination 435 can hold knob 240 in place when it is rotated into adesired position.

The function and location of the remaining components in FIG. 12 aredescribed below and/or shown in the attached Figures.

FIG. 4 illustrates a view of inside ventilator 110 in accordance with anembodiment of the presently described invention. FIG. 4A illustrates aview of one half of ventilator 110 housing 400 and of the insides ofventilator device 110 in accordance with an embodiment of the presentlydescribed invention. FIG. 4B illustrates a view of the other half ofventilator 110 housing 500 and of the insides of ventilator device 110in accordance with an embodiment of the presently described invention.

Insides 400, 500 of ventilator device 110 include a pressure regulator414, a solenoid 416, a plurality of tubes (referred to as first tube418, second tube 422, third tube 424, fourth tube 426, fifth tube 518,sixth tube 432 and seventh tube 415), a tube connector 420, one or moresolenoid 416 control wires 428, a flow control device 434, one or morepower source 320 wires 520, one or more electrical circuits 514, holes172, 512, a plurality of sensors (referred to as first sensor 516 andsecond sensor 522), and a plurality of clips 1260. Circuit(s) 514 is/arereferred to as circuit 514, regardless of whether circuit 514 comprisesone or more electrical circuits.

First sensor 516 can include a pressure switch configured to close whenthe measured pressure falls within a particular range. For example,first sensor 516 can include a pressure switch that closes when themeasured pressure is between 38 and 40 psi (262 and 275 kPa). Firstsensor 516 can be monitored for the low source pressure alarm describedabove. In an embodiment, first sensor 516 can include a printed circuitboard mount pressure and vacuum switch, such as the switch manufacturedby Presairtrol and designated by part number CSPEGA-10PR(60 4).

Second sensor 522 can include a pressure sensor capable of measuring arange of pressures and providing a voltage signal as output. Forexample, sensor 522 can measure a range of pressures from 0 to 60 cmH.sub.2O (0 to 5.9 kPa). In an embodiment, second sensor 522 can includean integrated silicon pressure sensor, such as the sensor manufacturedby Freescale Semiconductor, Inc. with the series number MPXV4006G.

As described above, a fluid source 120 is connected to ventilator 110via fluid source connection 130 and inlet valve connection 180.Regulator 414 is connected to inlet valve 180. Regulator 414 is alsoconnected to solenoid 416 and fourth tube 426. Regulator 414 isconnected to sensor 516 via tube 426.

Solenoid 416 is connected to regulator 414 using tube 415, one or morewires 428 and first tube 418. Solenoid 416 is electrically connected tocircuit 514 via wire(s) 428. Solenoid 416 is connected to flow controldevice 434 via first tube 418, connector 420, second tube 422 and thirdtube 424.

Connector 420 connects first tube 418 with second and third tubes 422,424. In an embodiment, connector 420 is a Y-connector.

Flow control device 434 is connected to tidal volume control knob 240,second tube 422, third tube 424, sixth tube 432 and output valve 170.Flow control device 434 is connected to solenoid 416 via tubes 418, 422and 424 and connector 420. Flow control device 434 is connected tocircuit 514 and sensor 516 via tube 432. Flow control device 434 is alsoconnected to patient 160 via output valve 170, patient circuitconnection 140 and delivery device 150.

FIG. 5A illustrates a perspective view of a back side and a top of flowcontrol device 434. FIG. 5B illustrates a perspective view of a frontside and a top of device 434. FIG. 5C illustrates a plan view of a sideof device 434. FIG. 5D illustrates a plan view of the back side ofdevice 434.

FIG. 6 illustrates a cross-sectional view of flow control device 434 inaccordance with an embodiment of the presently described invention. Flowcontrol device 434 includes a knob connector 610, an orifice controltube 615, an orifice plate 620, an orifice connection 625, a pressurerelief plate 630, a spring 635, a pressure relief outlet port 640, adiaphragm valve 645, an exhalation port 650, an input port 655 and anoutput port 660. An interior of device 434 also includes a plurality ofchambers and tubes through which pressurized fluid can pass through.These chambers and tubes include an entry chamber 665, a first tube 670,a middle chamber 675, a second tube 680 and a third tube 685.

In an embodiment, orifice connection 625 is sealed by one or moreO-rings surrounding connection 625. These o-rings can prevent or impedefluid from passing around, rather than through, connection 625.

Knob connector 610 includes any object or protrusion capable ofinterfacing with knob 240. For example, connector 610 can include anobject that fits inside of knob 240 so that rotating knob 240 alsocauses connector 610 to rotate.

Knob connector 610 is connected to tube 615. Tube 615 is also connectedto orifice plate 620. In this way, tube 615 connects knob connector 610to orifice plate 620. By turning knob 240 when it is connected toconnector 610, connector 610, tube 615 and orifice plate 620 alsorotate. In an embodiment, a plurality of connector 610, tube 615 andorifice plate 620 are integrally formed of the same material. That is, aplurality of these components is part of a single object and cannot beseparated from one another without damaging or destroying the object.

Input port 655 is in fluid communication with first chamber 665. By“fluid communication” or “fluidly connected,” it is meant that a fluidcan pass from the components, chambers and/or tubes that are soconnected. Therefore, a fluid such as pressurized 02 can pass from inputport 655 to first chamber 665. In an embodiment, input port 655 iscapable of being connected to tube 422. In this way, fluid travelingthrough tube 422 can enter into first chamber 665.

First chamber 665 is in fluid communication with first tube 670 viaorifice connection 625. Orifice connection 625 includes an orificeselected by rotating orifice plate 620 to a given position. As describedin more detail below, orifice plate 620 includes a plurality of orifices622 having a plurality of different diameters.

First tube 670 is in fluid communication with middle chamber 675. In anembodiment, device 434 includes a pressure relief apparatus. Thepressure relief apparatus includes pressure relief plate 630, spring 635and pressure relief outlet port 640. The pressure relief apparatus actsto relieve a build up of pressure in device 434. The pressure of thefluid traveling through device 434 can build up and push plate 630against spring 635. If the fluid pressure becomes large enough toovercome the force of spring 635 pushing plate 630 against the fluidpressure, plate 630 moves towards outlet port 640. When outlet port 640is moved far enough so that the fluid in middle chamber 675 can travelout of outlet port 640, the pressure in device 434 can decrease. Thefluid pressure in middle chamber 675 continues to decrease until theforce of spring 635 pushing plate 630 against the fluid pressureovercomes the fluid pressure. At that point, plate 630 closes the pathof the fluid from middle chamber 675 to outlet port 640 and the fluidtravels from middle chamber 675 to second tube 680.

The fluid travels from second tube 680 to third tube 685 and outlet port660. Outlet port 660 is configured to connect to valve 170. The fluidcan travel into outlet port 660, through valve 170 and into patientconnection circuit 140.

FIG. 11 illustrates orifice plate. 620 in accordance with an embodimentof the presently described invention. As shown in FIG. 11, orifice plate620 includes a plurality of orifices 622 each having a differentdiameter. As the diameter of each orifice 622 can affect the rate offluid flow through orifice plate 620, by changing which orifice 622 thefluid passes through device 434, the rate of flow of the fluid deliveredto patient 160 can be varied. That is, by rotating plate 620 to each ofa plurality of positions, each of the plurality of orifices can beplaced in a position to provide a connection (or orifice connection 625)between chamber 665 and tube 670. As the diameter of the orifice used inconnection 625 changes by a user rotating knob 240, the rate of flow ofthe fluid passing through device 434 and ventilator 110 can be varied.In an embodiment, orifice plate 620 can include one or more locations onplate 620 where no orifices 622 exist. That is, instead of having anorifice 622 in a location where one would normally be located, plate 620can be solid in that location. When this location is lined up withorifice connection 625, flow of the fluid through device 434 can beimpeded or blocked.

In an embodiment of the presently described invention, device 434includes an outlet port 690 useful for measuring a pressure of the fluidpassing through device 434. As shown in FIG. 10A and FIG. 10B, outletport 690 is in fluid communication with tube 680. Fluid travelingthrough tube 680 can also pass through outlet port 690. As describedbelow, fluid traveling through outlet port 690 passes into tube 432,which is configured to direct sufficient fluid in device 434 and/orpatient connection circuit (or patient airway connection) 140 to sensor522 so that sensor 522 can measure the fluid pressure in connectioncircuit 140 and/or device 434.

As shown in FIGS. 4, 4A, 4B and 5, ports 650, 655 and 690 can beconnected to tubes 424, 422 and 432, respectively. That is, tube 424 canbe placed onto port 650 to establish fluid communication between port650 and at least connector 420. Tube 422 can likewise be placed ontoport 655 to establish fluid communication between port 655 and at leastconnector 420. Tube 432 can also be placed onto port 690 to establishfluid communication between port 690 and sensor 522. By making theseconnections, fluid travel throughout ventilator 110. For example, fluidcan exit solenoid 416 and travel through tube 422. As tube 422 connectsto port 655, the fluid can enter device 434 via port 655.

In an embodiment, pressure relief outlet port 640 does not connect toany tube or connector. Outlet port 640 can instead direct fluidtraveling through it into interior of ventilator 110 or outside ofventilator 110 via one or more holes or other outlet(s) lined up withport 640.

Knob 240 and hole 512 are configured so that when the two halves 400,500 of ventilator 110 are combined together, or closed together, to formventilator 110 as shown in FIG. 1. Knob 240 can be accessible throughhole 512.

Valve 170 and hole 172 are configured so that when the two halves 400,500 of ventilator 110 are combined together, or closed together, to formventilator 110 as shown in FIG. 1. Valve 170 can be accessible throughhole 172.

Wires 520 connect one or more power sources 320 to circuit 514. Sensors516, 522 are each connected to or a part of circuit 514. In anembodiment, circuit 514 is a printed circuit board (“PCB”) housing oneor more electrical circuits. Using a PCB for circuit 514 makes theelectrical components of ventilator 110 more durable than existingventilators that include non-PCB based electrical components. Inaddition, the PCB can be sprayed or otherwise coated with an epoxy toadd further strength and durability to circuit 514 and thereforeventilator 110.

In an embodiment, circuit 514 is capable of comparing one or moremeasured quantities to one or more thresholds to determine if any of thealarms described above need to be activated. For example, circuit 514 isconnected to power source 320 by wires 520. From this connection,circuit 514 can obtain electrical power and measure the voltage, currentor time remaining in power source 320. In an embodiment, circuit 514 cancalculate the amount of time remaining by comparing a remaining amountof voltage in power source 320 and comparing this voltage to previoustesting results. The previous testing results can include tests on howlong ventilator 110 was able to run on a given amount of remainingvoltage. For example, during testing a given voltage remaining in powersource 320 can yield two hours of operation by ventilator 110. Circuit514 can calculate the amount of time remaining by comparing the existingamount of voltage in power source 320 and comparing it to the minimumvoltage required for two hours of operation.

In another example, one or more of sensors 516, 522 can determine ormeasure a fluid pressure and communicate the pressure to circuit 514.Circuit 514 can then compare the pressure to one or more thresholds(described above) and activate one or more alarms.

In an embodiment, circuit 514 includes a voltage step up circuit. Thevoltage step up circuit can increase the supplied voltage to circuit 514from power source 320. For example, circuit 514 can include a voltagestep up circuit that increases a voltage of 3.0 volts supplied by twosize “D” alkaline batteries to 5.0 volts. The 5.0 volts can then beapplied to selected electrical components.

In addition, in an embodiment circuit 514 is in communication with BPMbuttons 218 and inspiratory buttons 216. For example, electricalcontacts or connections between circuit 514 and buttons 216, 218 canprovide such communication. Circuit 514 can include programmable logicfunctionality that is capable of being simply programmed by a user. Forexample, circuit 514 can include one or more processors ormicroprocessors.

Circuit 514 can be capable of being controlled by a user pushing buttons216 and/or 218. As described in more detail below, a user can increaseand/or decrease the BPM administered to a patient 160 using buttons 218.When either of buttons 218 is depressed, circuit 514 changes the BPM, orfrequency, of the fluid supplied to patient 160. In an embodiment,circuit 514 is also capable of illuminating or displaying the selectedBPM in display window 212.

A user can also control the inspiratory time administered by ventilator110 to patient 160 using inspiratory buttons 216. By selecting one orthe other of buttons 216, a user can select whether a longer inspiratorytime is required for an adult or adult-sized patient 160 or a shorterinspiratory time is required for a child or child-sized patient 160, forexample. When a user selects one of buttons 216, circuit 514 changes theinspiratory time of the fluid administered to patient 160 by ventilator110. In addition, ventilator 110 can display the selected inspiratorytime. For example, circuit 514 can cause a light or LED next to one ormore of buttons 216 to become illuminated when that button 216 isselected.

In operation, a fluid source 120 is connected to ventilator 110 asdescribed above. Fluid source 120 is opened or otherwise enabled tosupply fluid, such as a pressurized gas, to ventilator 110 via inletvalve 180. Once the fluid enters ventilator 110, the fluid is directedto regulator 414. Regulator 414 regulates the input fluid pressure forventilator 110. In an embodiment, regulator 414 decreases the pressureof the input fluid. For example, regulator 414 can step down the inputfluid pressure to 40 psi (275 kPa). In addition, regulator 414 can serveto provide a more uniform pressure to orifice plate 622. By providing amore uniform pressure on orifice plate 622, the rate of fluid flowthrough ventilator 110 can be more consistent if the pressure of thefluid supplied by source 120 varies.

A portion of the fluid passes from regulator 414 to sensor 516. In anembodiment, sensor 516 measures or otherwise determines the pressure ofthe fluid input to ventilator 110. Sensor 516 can measure this pressureto determine if pressure of the fluid supplied by source 120 falls belowthe source pressure threshold described above. In an embodiment, sensor516 is powered by power source 320. If the pressure does fall below thisthreshold, sensor 516 can communicate this event with circuit 514, whichcan then activate an alarm. For example, the light next to the “lowsource gas alarm” on alarm panel 220 can be illuminated if the pressureof the source fluid drops below 40 psi (275 kPa).

A portion of the fluid also passes from regulator 414 to solenoid 416.Solenoid 416 acts as a valve that is capable of stopping or allowing theflow of the fluid to pass through ventilator 110. For example, solenoid416 includes a piston capable of moving between as least two positions.In an embodiment, one position of the piston permits the fluid to passthrough solenoid 416 and on through tube 418 while another position ofthe piston impedes this fluid flow or stops the flow completely.

FIGS. 7 and 8 illustrate schematic diagrams of solenoid 416 inaccordance with an embodiment of the presently described invention.FIGS. 7 and 8 illustrate simplified views of one embodiment of theoperation of solenoid 416. Other manners of operation of solenoid 416that achieve the same start/stop functionality (with respect to the flowof the fluid through ventilator 110) are also within the scope ofembodiments of the presently described invention.

Solenoid 416 includes a piston 610, a fluid flow path 620 and a pistontravel path 630. In an embodiment, piston 610 is capable of movingbetween a first position (shown in FIG. 7 and referred to as an “open”position) and a second position (shown in FIG. 8 and referred to as a“closed” position). Piston 610 can be moved between first and secondpositions using a voltage difference supplied by power source 320 and/orcircuitry 514. In an embodiment, a 1.5 volt differential moves piston610 between first and second, or open and closed, positions. The voltagedifferential, and therefore control of solenoid 416, can be provided viawire 418 connected to circuitry 514.

While piston 610 is in the open position, fluid is delivered to apatient 160 from ventilator 110. The fluid passes through solenoid 416via the fluid flow path 620 with piston 610 being generally out of flowpath 620.

When piston 610 is in the closed position, fluid is not being deliveredto patient 160 or the fluid flow is greatly impeded. That is, fluid flowpath 620 is partially to completely blocked by piston 610. In otherwords, while the closed position may not completely block the flow ofall fluid from source 120 to patient 160, the closed position causessolenoid 416 to prevent a majority of fluid flow from reaching patient160. In an embodiment, all fluid flow through path 620 is blocked bysolenoid 416 when it is in the closed position. In such an embodiment,solenoid 416 includes a barb 436, as shown in FIGS. 4 and 4A. Barb 436is an outlet such as a tube or other opening in solenoid 416. Barb 436provides an outlet port that can vent the pressure in connection 140 andpermit delivery device 150 to open and permit patient 160 to exhale.

In an embodiment, piston 610 is capable of only being in the open orclosed position. That is, piston 610 is incapable of being halfwaybetween the open and closed positions. In such an embodiment, solenoid416 is only capable of permitting or blocking/impeding fluid flowthrough ventilator 110. In other words, solenoid 416 cannot be at aposition other than the open or closed position.

Once fluid passes through solenoid 416 (assuming solenoid 416 is in anopen position), the fluid travels through tube 418 to connector 420.Once fluid reaches connector 420, the fluid passes through connector 420into tubes 422 and 424. From tubes 422, 424, the fluid travels into flowcontrol device 434. In doing so, the path of the fluid travels firstthrough solenoid 416 and then through flow control device 434. In otherwords, solenoid 416 is “upstream” from flow control device 434 and flowcontrol device 434 is “downstream” from solenoid 416.

Solenoid 416 and flow control device 434 can operate together to make iteasier for patient 160 to exhale. FIG. 13 illustrates a cross-sectionview of flow control device 434 in accordance with an embodiment of thepresently described invention. Device 434 as illustrate in FIG. 13 issimilar to the embodiment illustrated in FIGS. 5 and 6. One differenceis that device 434 in FIG. 13 includes a hole 647 connecting a chambersurrounding diaphragm valve 645 with the atmosphere surrounding flowcontrol device 434. Hole 647 can assist in opening and/or closingdiaphragm valve 645. In combination, hole 647 and diaphragm valve 645can work together to vent patient connection circuit 140 and thus makeit easier for patient 160 to exhale.

In operation, when solenoid 416 is in the open position, fluid flowsfrom solenoid 416 into ports 650 and 655. As fluid flows into port 650,the fluid pushes diaphragm valve 645 to close. When diaphragm valve 645is closed, fluid cannot pass or is impeded from passing from port 650 totube 685 and hole 647. Instead, fluid passes from tube 685 into outletport 660 and then into patient connection circuit 140. As fluid passesinto connection circuit 140, one-way valve 157 remains open so that thefluid can be provided to patient 160 via patient connection circuit 140and delivery device 150.

When solenoid 416 is in the closed position, fluid flows out of barb 436of solenoid 416 and does not pass into port 650. When fluid does notflow into port 650, the fluid pressure forcing diaphragm valve 645closed decreases or no longer exists. If the fluid pressure forcingdiaphragm valve 645 drops to a sufficiently low level, diaphragm valve645 opens. Once diaphragm valve 645 opens, hole 647 can provide a pathof fluid communication between the atmosphere surrounding flow controldevice 434 and tube 685 (and therefore output port 660 and patientconnection circuit 140, as each of tube 685, port 660 and circuit 140are connected). The fluid pressure in patient connection circuit 140 isthen vented through outlet port 660, tube 685 and hole 647 into theatmosphere surrounding flow control device 434. Once the fluid pressurein patient connection circuit 140 decreases a sufficient amount, one-wayvalve 157 closes. When valve 157 closes, patient 160 can exhale throughexhalation port 155.

In an embodiment, tube 432 is in communication with patient connectioncircuit 140 via flow control device 434. Tube 432 is also connected tosensor 522. Tube 432 is configured to direct sufficient fluid in patientconnection circuit (or patient airway connection) 140 and/or in device434 to sensor 522 so that sensor 522 can measure the corresponding fluidpressure. Once sensor 522 measures or otherwise determines the fluidpressure, circuit 514 can compare this pressure to a threshold, such asthe upper airway pressure threshold and/or the lower airway pressurethreshold described above. If the fluid pressure in connection circuitor airway connection 140 exceeds the upper airway pressure threshold,for example, circuit 514 activates one or more alarms, as describedabove. If the fluid pressure in airway connection 140 is lower than thelower airway pressure threshold, for example, circuit 514 activates oneor more alarms, also as described above. In an embodiment, an alarmincludes illuminating the light next to the text “HIGH AIRWAY PRESSUREALARM” on alarm control panel 220.

In addition, circuit 514 can cause the fluid pressure in airwayconnection 140 to be displayed to a user in window 214 of ventilator110.

In an embodiment, a timing control device of ventilator includessolenoid 416, at least a functional portion of circuit 514 and powersource 320. By “functional portion,” it is meant that the part(s) orportion(s) of circuit 514 that controls whether solenoid 416 is in anopen or closed position is the functional portion of the timing controldevice.

The timing control device controls the frequency (or BPM) and duration(or inspiratory time) of breaths administered by ventilator 110 using anelectrical power source 320 and solenoid 416. In this manner, the timingcontrol for ventilator 110 is electronically controlled. The functionalportion of circuit 514 related to the timing control device determines,based on user input, the selected BPM and/or inspiratory time to be usedin supplying the fluid to patient 160. As described above, this userinput can be a user pushing BPM buttons 218 and/or inspiratory buttons216.

Based on the BPM and/or inspiratory time selected by the user, circuit514 determines the rate, or frequency, at which solenoid 416 shouldswitch between open and closed positions. As described above, whensolenoid 416 is in an open position, fluid is being delivered to patient160. Conversely, when solenoid 416 is in a closed position, fluid is notbeing delivered to patient 160. Circuit 514 can control whether solenoid416 is in an open or closed position by varying a voltage differentialacross solenoid 416. For example, by varying the voltage supplied tosolenoid 416 using wire(s) 428 by 1.5 volts, circuit 514 can causesolenoid 416 to change between open and closed positions.

For example, if a BPM of ten is selected by a user (indicating tenbreaths per minute), then circuit 514 can determine that solenoid 416should open and close once every six seconds to cause ventilator 110 todeliver ten breaths in a minute. If a BPM of thirty is selected, circuit514 can determine that solenoid 416 should open and close once every twoseconds to cause ventilator 110 to deliver thirty breaths in a minute,for example. If a BPM of five is selected, circuit 514 can determinethat solenoid 416 should open and close once every twelve seconds tocause ventilator 110 to deliver five breaths in a minute, for example.

In another set of examples, if an inspiratory time of one second isselected by a user (indicating that the inspiratory time, or fluiddelivery time, should last for one second), then circuit 514 candetermine that solenoid 416 should open and remain open for one secondbefore closing at each breath delivered by ventilator 110. If aninspiratory time of two seconds is selected, circuit 514 can determinethat solenoid 416 should open and remain open for two seconds beforeclosing at each breath delivered by ventilator 110, for example.

Thus, circuit 514 can electrically control solenoid 416 to vary thefrequency and duration of breaths supplied to patient 160 by ventilator.For example, with a BPM of ten and an inspiratory time of two secondsselected, circuit 514 can cause solenoid 416 to open and close ten timesper minute and remain in an open position each time it opens for twoseconds. By providing electronic control of the timing of breathsprovided by ventilator 110, the timing control device of ventilator 110provides a more accurate and precise manner of controlling the BPM andinspiratory time. As the timing control device does not rely on source120 fluid pressure to operate (as some existing ventilators do), butinstead rely on relatively long-lasting power source(s) 230, the timingcontrol device has a greater accuracy and precision as long as anadequate power source 230 remains. That is, as the pressure of a source120 fluid can vary to a greater extent than the voltage supplied byalkaline battery power sources 230, for example, ventilators that relyon source fluid pressure can experience greater fluctuations in theirbreath timing control (such as BPM and inspiratory time) than ventilator110.

Another component of ventilator 110 is flow control device 434. Flowcontrol device 434 enables a user to control and vary the rate at whichthe fluid is supplied to a patient 160 during the inspiratory time (ortime at which solenoid 416 is in an open position). As described above,flow control device 434 controls the rate at which the fluid isdelivered to a patient 160 using a plurality of orifices of differentdiameters. A user selects which orifice is to be used by turning knob240 to a desired tidal volume (as shown in FIGS. 1 and 2). Markings onan outside surface of ventilator 110 can indicate which orifice isselected. A marking 242 on knob 240 can be employed by a user to selectthe desired orifice and tidal volume. In general, selecting a largertidal volume causes a greater rate of fluid flow through flow controldevice 434 and to patient 160.

As described above, flow control device 434 does not rely on anyelectricity, electric power source or electrical circuits. Thus, device434 does not rely on, and is not controlled or otherwise dependent uponpower source 230 and circuit 514. As a result, device 434 is essentiallya pneumatic flow control of ventilator 110, and is generally more robustand durable than electrically controlled flow controls in existingventilators.

Using flow control device and the timing control device, a user can veryaccurately and precisely control the volume of fluid delivered to apatient by ventilator 110. That is, the user can control the BPM andinspiratory time that a selected rate of fluid is provided to a patient160. As a result, the separate timing control device and flow controldevices of ventilator 110 permit a user to electronically control a timeperiod at which a selected rate of fluid flow is provided to patient160.

As described above, ventilator 110 includes a timing control device thatoperates off a low voltage power circuit. This timing control device canbe powered by relatively longer lasting, light, small, inexpensive andreadily available alkaline batteries, for example. This improves overexisting ventilators that rely on relatively heavy, large and expensivelead acid batteries that have a relatively shorter life and arerelatively difficult to find (especially in emergency situations). Thisdesign of ventilator 110 can reduce its overall weight compared toexisting ventilators and can increase the operating time of ventilator110 over existing ventilators.

Moreover, by separating the timing control device and flow controldevice 434 into separately controlled devices operated electrically andpneumatically, respectively, ventilator 110 can provide increasedaccuracy and precision in BPM and inspiratory times for fluids providedto patients 160. Existing ventilators may include all pneumatic systemsto control fluid flow and timing. Such ventilators typically includecomplex pneumatic systems that rely on the build up of source fluidpressure as a timing function (or as a timing control device). But,small leaks and slight variations common in these ventilators can affectthe performance, accuracy and precision of the ventilators.

In addition, some existing ventilators are entirely electronicallycontrolled. Such ventilators use electronic circuits to control thetiming and to control and drive a complex proportioning valve toestablish flow control of fluid through the ventilator. Such ventilatorstypically require more power or voltage than embodiments of ventilator110. In addition, these ventilators typically require additionalhardware such as position feedback circuits to obtain improved accuracyin their timing.

FIG. 9 illustrates a flowchart of a method 900 for using an improvedventilator 110 in accordance with an embodiment of the presentlydescribed invention. Method 900 begins at step 905, where a fluid sourceis connected to the ventilator. For example, a source 120 can beconnected to ventilator 110 as described above.

Next, at step 910 a patient airway connection is connected to theventilator and to a patient. For example, patient airway connection 140can be connected to ventilator 110 and patient 160 as described above.

Next, at step 915, a BPM, inspiratory time and rate of fluid flow areselected. For example, a user can select a desired BPM and inspiratorytime using buttons 216, 218 and can select a rate of fluid flow byturning knob 240 to a desired tidal volume, as described above.

Next, at step 920, the fluid flows from the fluid source into a timingcontrol device of the ventilator. For example, the fluid can flow fromsource 120 into solenoid 416, as described above. In an embodiment, thefluid can flow into a pressure regulator, such as regulator 414, priorto flowing into the timing control device.

Next, at step 925, method 900 proceeds to either step 930 or step 935depending on whether the timing control device is open or in an openedstate. If the timing control device is open, then method 900 proceedsfrom step 925 to step 935. If the timing control device is closed, thenmethod 900 proceeds from step 925 to step 930. For example, if solenoid416 is in an open state or position, method 900 can proceed from step925 to step 935. If solenoid 416 is in a closed state or position,method 900 can proceed from step 925 to step 930.

At step 930, the fluid does not pass through the timing control device.That is, the timing control device blocks or at least impedes a majorityof the fluid flow through the timing control device. For example,solenoid 416 can block or impede the flow of the fluid through solenoid416. Method 900 proceeds from step 930 back to step 925, where it isdetermined whether the timing control device is open. In doing so,method 900 proceeds in a loop including steps 925 and 930 until thetiming control device is in an open position or state.

At step 935, the fluid passes through the timing control device and intothe flow control device. For example, as described above, the fluid canpass into flow control device 434 after passing through an open solenoid416.

Next, at step 940, the flow control device varies the rate of fluidflow. That is, the flow control device can increase or decrease the rateof fluid flow. In an example, flow control device 434 includes aplurality of orifices having different diameters. Flow control device434 can direct the flow of fluid through one or more of these orificesto change the rate of fluid flow, as described above.

Next, at step 945, the fluid is supplied to a patent. For example, thefluid can be supplied to a patient 160 after passing through flowcontrol device 434 via a patient airway connection 140.

While particular elements, embodiments and applications of the presentlydescribed invention have been shown and described, it is understood thatthe presently described invention is not limited thereto sincemodifications may be made by those skilled in the technology,particularly in light of the foregoing teaching. It is thereforecontemplated by the appended claims to cover such modifications andincorporate those features that come within the spirit and scope of thepresently described invention

What is claimed is:
 1. A ventilator apparatus comprising: anelectrically powered timing control device configured to control aperiod of time that a fluid is delivered to a patient during inspiratorytime periods, the timing control device including a solenoid and anoutlet, the timing control device configured to be adjusted to changethe inspiratory time periods that the fluid is delivered to the patient,the timing device configured to move the solenoid to a position to blockflow of the fluid to the patient during times between the inspiratorytime periods; and a flow control device configured to control a rate offlow that the fluid is delivered to the patient, the flow control deviceincluding plural orifices configured to be adjusted to change the rateof the flow that the fluid is delivered to the patient during theinspiratory time periods.
 2. The ventilator apparatus of claim 1,wherein the timing control device is disposed upstream of the flowcontrol device along a pathway that the fluid flows to the patient. 3.The ventilator apparatus of claim 1, wherein the timing control deviceis configured to control durations of the inspiratory time periods byactuating the solenoid to an open position or a closed position, theinspiratory time periods beginning when the solenoid is actuated to theopen position and ending when the solenoid is actuated to the closedposition, the solenoid configured to permit flow of the fluid to thepatient when the solenoid is at the open position and to prevent theflow of the fluid when in the closed position.
 4. The ventilatorapparatus of claim 1, wherein orifices have different diameters.
 5. Theventilator apparatus of claim 1, wherein a volume of the fluid providedto the patient by the timing control device and the flow control deviceis capable of being altered by manually adjusting one or more of theinspiratory time periods using the timing control device or by manuallyadjusting the rate of flow using the flow control device.
 6. Theventilator apparatus of claim 1, wherein the flow control deviceincludes an inlet that is configured to be fluidly coupled with thetiming control device to receive the fluid from the timing controldevice, a first outlet fluidly configured to be fluidly coupled with thepatient to deliver the fluid to the patient, and a different secondoutlet, and further comprising a patient airway pressure sensorconfigured to be fluidly coupled with the second outlet of the flowcontrol device, the pressure sensor configured to measure a pressure ofthe fluid delivered to the patient through the first outlet of the flowcontrol device based on at least some of the fluid that flows to thepressure sensor through the second outlet of the flow control device. 7.The ventilator apparatus of claim 6, further including at least onealarm communicatively coupled with the pressure sensor and configured toprovide at least one of a visual notification or an audible notificationwhen at least one of several alarm events occurs.
 8. The ventilatorapparatus of claim 7, wherein the alarm events include one or more of:the pressure of the fluid exceeding an upper airway pressure threshold;the pressure of the fluid falling below a lower airway pressurethreshold for at least a predetermined period of time; or the pressureat which the fluid is supplied by the fluid source falling below asource pressure threshold.
 9. The ventilator apparatus of claim 6,wherein the second outlet of the flow control device does not direct thefluid to the patient.
 10. A ventilator apparatus comprising: aninspiratory timing control device configured to be fluidly coupled witha patient airway connection that delivers a fluid to a patient, thetiming control device configured to start and stop a flow of the fluidto the patient through the patient airway connection, the timing controldevice configured to receive manual input from an operator that directsthe timing control device when to start or stop the flow of the fluid tothe patient; a flow control device configured to be fluidly coupled withthe timing control device and with the patient airway connection, theflow control device having a first outlet configured to be fluidlycoupled with the patient airway connection, plural orifices havingdifferent sizes, and a different second outlet, the flow control deviceconfigured to receive the fluid from the timing control device andcontrol a rate of the flow of the fluid to the patient through the firstoutlet and the patient airway connection; and a patient airway pressuresensor fluidly coupled with the second outlet of the flow controldevice, the patient airway sensor configured to receive at least some ofthe fluid passing through one or more of the orifices of the flowcontrol device and exiting the flow control device through the secondoutlet, the pressure sensor configured to measure a pressure of thefluid delivered to the patient based on the fluid received from thesecond outlet.
 11. The ventilator apparatus of claim 10, wherein thetiming control device is configured to calculate a time period requiredto deliver a desired tidal volume of the fluid to the patient at amanually selected rate of fluid flow based on the manual input.
 12. Theventilator apparatus of claim 10, wherein the timing control device ispowered by one or more replaceable batteries.
 13. The ventilatorapparatus of claim 10, wherein the timing control device is configuredto start and stop the flow of the fluid to the flow control device at apoint upstream from the orifices in the flow control device.
 14. Theventilator apparatus of claim 10, wherein the timing control deviceincludes a solenoid and an outlet, the timing control device configuredto move the solenoid to a position to block flow of the fluid to thepatient with the fluid flowing through the timing control devicedirected away from the patient and out of the timing control devicethrough the outlet of the timing control device when the solenoid blocksthe flow of the fluid.
 15. A method of providing a ventilator apparatus,the method comprising: fluidly coupling an inspiratory timing controldevice with a patient airway connection that delivers a fluid to apatient, the control device configured to start and stop a flow of thefluid to the patient through the patient airway connection; fluidlycoupling a flow control device with the timing control device and withthe patient airway connection, the flow control device having a firstoutlet configured to be coupled with the patient airway connection andplural orifices having different sizes, the flow control deviceconfigured to receive the fluid from the timing control device andcontrol a rate of the flow of the fluid to the patient through the firstoutlet and the patient airway connection; and fluidly coupling a patientairway pressure sensor with the flow control device, the patient airwaysensor configured to receive at least some of the fluid passing throughone or more of the orifices of the flow control device and exiting theflow control device, the pressure sensor measuring a pressure of thefluid delivered to the patient based on the fluid received from thesecond outlet.
 16. The method of claim 15, wherein the timing controldevice is fluidly coupled with the patient airway connection such thatat least some of the fluid is directed out of the timing control deviceand away from the patient through an outlet in the timing control devicewhen the timing control device stops the flow of the fluid to thepatient through the patient airway connection.
 17. The method of claim15, wherein fluidly coupling the flow control device includes fluidlycoupling the flow control device such that a desired tidal volume isdelivered to the patient at a selected rate of fluid flow through theflow control device, the flow control device configured to calculate atime period required to deliver the desired tidal volume at the selectedrate of fluid flow based on the manual input and controlling a start andend to the time period by moving a solenoid between first and secondpositions.
 18. The method of claim 15, wherein fluidly coupling the flowcontrol device includes fluidly coupling the flow control devicedownstream of the timing control device such that the timing controldevice is configured to start and stop the flow of the fluid at a pointupstream from the plurality of orifices in the flow of the fluid throughthe flow control device.
 19. The method of claim 15, further includingproviding at least one of a visual and audible notification when atleast one of plural alarm events occurs, the alarm events including: thepressure in the patient airway connection exceeding an upper airwaypressure threshold, the pressure in the patient airway connectionfalling below a lower airway pressure threshold, the pressure at whichthe fluid is supplied by the fluid source falling below a sourcepressure threshold, a level of a power source of the timing controldevice falling below a power source threshold.
 20. The method of claim15, wherein further comprising electronically controlling a period oftime that the fluid is supplied to the patient using the timing controldevice by moving a solenoid between an open position and a closedposition.